Severe COVID-19 linked to increased risk of stillbirth, preterm birth

A new data analysis links COVID-19 to increased risk of pregnancy complications including preterm birth and stillbirth, with the risks rising if infection is severe.

Montreal researchers conducted a meta-analysis of 42 studies involving 438,548 pregnant people around the world.

Authors including Dr. Nathalie Auger of the University of Montreal's School of Public Health said the data "provides clear evidence that symptomatic or severe COVID-19 is associated with a considerable risk of preeclampsia, preterm birth and low birth weight."

"Clinicians should be aware of these adverse outcomes when managing pregnancies affected by COVID-19 and adopt effective strategies to prevent or reduce risks to patients and fetuses," concludes the study, published Friday in the Canadian Medical Association Journal.

The study says COVID-19 patients were more likely than those without the disease to experience preeclampsia, stillbirth and preterm birth.

Urgent questions for medical community

Compared to asymptomatic patients, symptomatic patients were at double the risk of preterm birth and a 50 per cent increased risk of cesarean delivery.

Meanwhile, those with severe COVID-19 had a four-fold higher risk than those with a mild case to experience high blood pressure and preterm birth.

The reason for increased risk was unclear, but researchers said it could be because the virus that causes COVID-19 stimulates an inflammatory response affecting blood vessels.

The team also called for more research to better understand disease pathways that explain these associations.

"Lack of knowledge about SARS-CoV-2 infection in pregnancy has raised urgent questions among obstetricians and neonatologists about the risk of maternal, fetal and neonatal morbidity and mortality," the study says.

"There is an urgent need for evidence to guide clinical decisions."

The Society of Obstetricians and Gynaecologists of Canada (SOGC), has said all governments should grant access to the COVID 19 vaccine to pregnant and lactating individuals.

"The benefits of getting vaccinated for individuals at higher risk during pregnancy or while breastfeeding outweighs the risks of not receiving the vaccine," SOGC said.